Compressor



March 2, 1943. F. A. HALLECK 2,312,335

' COMPRESSOR Filed April 24, 1939 7 Sheets-Sheet 1 March 2, 1943; F. A. HALLECK 1 2,312,335

' COMPRESSOR Filed April 24,1939 '7 Sheets-Sheet 2 l ll f y /////II//////////////M I I v v I' n l I I l l I l I I l I IIIIIIIIIIIIIIIII l I l I l I g i,

March 2, 1943. F. A. HALLECK 2,312,335

COMPRESSOR Filed April 24, 1939 v sheets-sheet 3 March 2, 1943. I F. A..HLALILECK I 2,312,335

COMPRESSOR Filed April 24, 1939 7 Sheets-Sheet 4 March 2, 1943. F. A. HALLECK 2,312,335

' COMPRESSOR Filed April 24, 19:59 'Z'Sheets-Sheet 5 In vnior: flank 0.1%226676.

Patented Mar. 2; 1943 UNITED STATES PATENT amass-5* Frank A: Halleck Michigan. City; to

Sullivan Machinery Company, a: corporation of Massachusetts Application lipriiz i, 1939," sari-amt; ziigcio" 8Glaimsz" My invention relates to fluid. compressors; and more particularly to improvements in compound compressors and in driving, cooling, and unloading means therefor.

An object of my invention is toxprovide an improved compressor. Another object of" my' invention is to provide an improved compound compressor that is exceedingly compact and highly efiicient. A further object of my invention is to provide an improved compound com pressor having improved cooling means for the compressed fluid. Yet another object is to pro: vide an improved compressor having improved cooling means for the lubricating fluid. other objects and advantages of my invention will hereinafter more fully appear.

In the accompanyin drawingsin which, sev eralembodiments of different aspects ofmy invention have been shown,

Fig. 1 is a front elevationalviewof' a multi stage compressor in which one illustrative form of invention is incorporated.

Fig. 2 is a. side elevational view of the com pressor shown in Fi 1.

Fig. 6 is a plan view, partially in section, of the compressor shown in Fig. 1.

V Fig. l is an enlarged horizontal sectional view through the crank case of the compressor shown in -Fig. 1, the section being taken on the'hori-- zqntal plane corresponding to the line l i'of Figs 1 and 5.

Fig. 5 is an enlarged View, partially in eleva tion and partially in vertical section, through the compressor shown in Fig. 1.

Fig 6 is a sectional view on the planes-"of theline 66 of Fig. 5.

'7 is an enlarged horizontal sectional view through an unloading control device and a portion ore. high pressure cylindenthe section being taken on the plane of theline of Fig. 2.

Fig. 8 is a schematic diagram showing the compressor cylinders and the unloading contro'l mechanism therefor. y

Fig. 9 is a sectional view similar to Fig; 5;

showing a modification of the invention.

Fig. l0is asectional-view on'the planes" of theline lll-I 0 of Fig. 9. n Fig. 11 is a sectional view similar to Fig.9;

showing another modification of the invention;-

Fig. 12 is a sectional view on the planes of" mennelz lz of Fig. 11; v

Iri'th'e "illustrative embodiment of the inven tion shown in Figs. 1 to 8 inclusive, thereis showrfia compound compressor having" a" base frame 'I on which are mounted at opposite sides of a: vertical. plane and-sf approximately;-

a; horizontal plane,y.two1 lowflpressure: cylinde 2 and 3; and on; aihorizontakplanef but: extend: ing fromv the .basexframei atpanangle. .of 1 30? apart, 'two'highpressure cylinders 4 and 5. g Fluid is supplied to the low pressurewylinders" from intake lines .6 and" 1'; branching. from .23.: commonintake line; 8 and -communicating with". case ings 9"}1'116. 10;- which; contain intake.- closure valves" l for controlling?- the: admission- 0f. .fluijd to;- the' cylinders. Extending: centrally through the; intake closure: valves;;.ar.e; valve-stems, J2 which are: connected; to; pistons. l3: reciprocably mounted in. cylinders I 4. formedrwithin the case ings 9 and- U1; The: valves are normally; held in; pen" posi ion :by; spr.ings ..l 5;- thereby permit:- ting fluid-to flow freely:throughpassages. .I6...in connections I1, and I8; to inlet .valves;.l9- and in the" head and crankkendsjof; the low prese sure; cylinders. The intake.;.closure.. valves are limited in their opening;- movement by adjustable stop membersqzlg andi arejactuated' to..closed position by fluid pressure conducted; .to the. cyl-; inders; l4 throughpipes 22 and 23.... Fluid is compressed in, the low pressure cylinders and dischargedzthrough-;discharge valves 213i and. 49 and connections -and, 3|- to intcrcoolers; 3 and 33, which are arrangeoliin.axialgalinement in the same Series of horizontal planes with .the low pressure cylinders; and with their adiiacen s. abuttin iea hpther andz'fastened together; as by bolts 3,4; The intercoolers. are; identical in; constructioniand contain 1 longitudinally ex1-'-. tending tubesi forconductinga cooling: fluid; such" as water; and battle plates; .36 extending transversely .to the tubes 35gdirectjthe con 1-, pressed fluid in; a" circuitous path, th'rough'the interccolersand across the coolingtubes;

The. compress d: fluid .f 0 s from the. inter: coolers through-connections 3.1 and 38.. toithe high pressure; cylinders-A and 5, through; inlet. valves 39; and 40. The fluidqis compressed a ain n eh pressure: cylinders and discharged through; dis h rg .-.va ves-'-4l and 42 ,tordischarge ipes- 3; and 4.4. t at conduct. the fluid-to; a. re CQiVeIT QlOtf' shown). Reciprocably mounted in the-low pressure cylinders are pistons 45; and. in the high; pressure; cylinders are? pistons; 46.; The pistons 45. and '46 are, connected by; pis'ton' 1 rods 4] to crossheads'48.reciprocably g-uidediin crpsshead guides ;;49 suitably supportednin seats formed; in the "base 1 frame," I... Connectingr rods 51!;connect the cross'heads jto'ra 'common:"crank pin 5!- carried by a'crankshaft 5| journaled at one end in a bearing 52 carried by a plate '53 attached to the side of the base frame, and journaled at its other end in bearings 55 and 50 supported by the base frame I. Attached to the side of the base frame, beneath the alined intercoolers and in axial alinement with the crankshaft, is an electric motor 51 having its rotor 58 keyed to the end of the crankshaft for driving the crankshaft and through it the compressor pistons 45 and 46.

Formed in the lower portion of the base frame is a chamber 59 containing oil for lubricating the moving parts of the compressor. A partition 60 extending centrally across the chamber divides the chamber into spaces BI and 92, and an opening 03 in the partition adjacent the bottom of the chamber provides for circulation of oil between the spaces GI and 62. A means is provided for cooling the oil in the chamber and comprises a pipe 64, shown arranged in the space 62, for conducting a coo-ling fluid, such as water. Baffle plates 05, and fins 65 formed integral with the base frame, direct the oil across the cooling pipe 64 and through the opening 63 to the space 6|, whence it is drawn through a strainer 61 and a pipe 08 and pumped by a suitable lub-ricator L through tubes not shown to parts of the compressor to be lubricated.

In this form of the invention, means is provided for effecting a step-by-step unloading of the compressor in accordance with compressor discharge or receiver pressure. This means comprises pilot valves 69, I0, 'II and I2, which may be of any suitable type, and which are herein illustrated as so-called RC pilot valves, arranged to control communication between the compressor discharge line or a receiver and pipes I3, 14, I

22 and 23, and between said pipes and the atmosphere. Pipe I3 communicates with pipes TI and I8 connected to suitable valve opening devices '19 and 80 for opening an inlet valve in one end of the low pressure cylinder 2 and an inlet valve in oneend of the high pressure cylinder 4. Pipe I4 communicates with pipes 8I and 82 connected to inlet valve opening devices 83 and 84 in the low pressure cylinder 3 and the high pressure cylinder 5. Pipes 22 and 23 communicate respectively, as explained above, with cylinders I4 controlling theintake closure valves for the low pressure cylinders 2 and 3.

With nothing more than the structure already described, the high pressure cylinders would, so long as any way available, take in fluid from their respective intercoolers to the ends of the cylinders, where the inlet valves are allowed to operate in 'a normal manner, after the intake closure valves are closed. Thus, if there were any leakage past the intake closure valves fluid might be drawn into the high pressure cylinders at quite low pressure, Any fluid taken in during unloaded operation would certainly be at a lower pressure than when the compressor operates loaded, and its compression to receiver pressure would result in an increased generation of heat. To avoid this, means are provided for automatically venting the ends of the high pressure cylinders to atmosphere when a partial vacuum exists in the intercoolers. Automatic vent control devices 90 and SI are attached to the sides of the high pressure cylinders 4 and 5, and as shown in Fig. 7, in the sectional view of the control device 9I attached to the high pressure cylinder 5, there is formed within the device a diaphragm chamber 92 having a diaphragm 93 therein. A space 94 within the chamber at one side of the diaphragm is open to atmosphere through an opening 95,

and a space 96 in the chamber at the other side of the diaphragm is connected to the intercooler 33 through a pipe connection 91. Formed in the walls of the high pressure cylinder are chambers 98 and 99 connected together by a passage I00. Supported in the chambers 98 and 99 at the ends of the high pressure cylinder are plates IM and I02 provided with small passages I03 and I04 opening into the cylinder bore and controlled by check valve mechanisms I05 and I06. In the passage I00 is a valve guard I07 supporting a spring I08 that acts to hold a valve I09 in position to close a passage IIO opening through a, plate III attached to the wall of the cylinder. A rod II2 clamped to the diaphragm 93 extends through an opening I I3 in the device 9| and the passage IIO to unseat the valve I09 against the pressure of the spring I98 when the diaphragm 93 moves to decrease the size of chamber 90. A chamber H4 in the device 9I is open to atmosphere through a pipe connection H5 and communicates with the valve controlled passage H0.

The mode of operation of this form of the invention is as follows.

Assuming that the receiver pressure is low and the compressor is operating fully loaded, air will be taken into the low pressure cylinders 2 and 3 through intake connections 6 and I, and be compressed and discharged to the intercoolers 32 and 33. The compressed air is taken from the intercoolers 32 and 33, passing across the tubes 35 and through discharge connections 31 and 38 to the high pressure cylinders I and 5. The air is compressed again in the high pressure cylinders and discharged through discharge connections 43 and 44 to a receiver (not shown). If the demand for air is low and the pressure in the receiver attains a predetermined value, the pilot valve 09 operates to admit pressure fluid to the pipe 13 and through pipes I1 and I8 to the inlet valve opening devices I9 and in the low pressure cylinder 2 and the high pressure cylinder 4, thereby effecting the first step of unloading. If the receiver pressure continues to increase, it will, at a predetermined higher pressure, operate the pilot valve II to supply pressure fluid through pipe 22 to the cylinder I4 and close the intake closure valve in the low pressure cylinder 2. On a still higher increase in receiver pressure, the pilot valve I0 operates to admit pressure fluid to the inlet valve opening devices 83 and 84 in the low pressure cylinder 3 and the high pressure cylinder 5, thereby efiecting a three-quarter unloading of the compressor. On a still higher increase in receiver pressure, the pilot valve I2 operates to admit pressure fluid to the cylinder I4 in the casing I0 to move the intake closure valve in the low pressure cylinder 3 to its closed position and completely unload the compressor. As soon as a partial vacuum is created in the intercoolers by the pumping of fluid in the not-directly-unloaded ends of the high pressure cylinders after the intake closure valves are closed, the vent control devices and 9I operate in the following manner to Vent the ends of the high pressure cylinders. Considering the control device 9I, it will be noted that a partial vacuum will exist in the space 96 due to its connection with the intercooler 33 through pipe 91, and the higher pressure in the space 94 will move the diaphragm 93 against the reduced pressure in the space 96 to open the valve I09 and connect the passage I00 to atmosphere through the passage IIO, chamber H4 and atmospheric connection II5. Any material compression of air in the high presurecrl ndesifiwilhthenpcen :t eiralves :51am; I081to connect the ends of thewhighepressu-re; crlindere-t rpu ht-zthe imbe s. 8rande98=iand the e sase l 00-. -t0.:atmosnhere.

Iii-thew d mand if rtain;incneasesrandrthe .re ceiver pressure LIIFQDJ$Q a.-;predetermine 1188.1; sure-, t'jihevp lot :valve II 2. operates: to vent; PIES. sure;-;-;fr,om-, the cylinder;-.-I4 ssassoeiatedzcwith.:the; cylin and; the..-intake. closure. valved! I. .conz;

tnolling;;admi,ssi0n .Ofr all .to .the; slow spte sllrei 10.

ventscommunicationa.betweenethecylinder-25:and-i the chambers 98 and been Air is thenpompressedc inaones ndzof; thelQW pnessnrecylinderii and ind one end.of. thezhieh..pressure ,.cy-1inder.;5 "and. .dlS::-.. charged; to. the receivers; At, :a :IOWeX! predete minedipressure in :the. receiyer,;:the. pilot .valve .1 in operates; :to -.vent f pressure';=fiuid; from. the. inlet-2. valve'ppe msdevices: 83.and 84,;51'1'81161337 ipermi-ta. tlnettheeinle wval-vesdmtheaends;of. the low .ipresat sure cylin em and .the.-:high p e snrewylinden i5 1; 35,,

I Q.:0per-ate.;in a normal manner. Ifithereceiveru pressure zdropvszto. a still loweripressure', the..-.pilotri valve TII operates to vent pressure from;the cylinder l4, andthe intake closure valve :for. the .lovsrc pressure cylinder 2 opens Air. is .-compressed 0.;

The compressed. air -flows.;-:.through.-.=the e inten a ain in one. end of the low. pressure.-cylinder-.2,;1 anddf the. venting. device 190 for, the high pres=.. sure cylinder 4 had previously operated ,to; vent-ethe cylinder to atmosphere, it, ;wi1l,: 011x211 ill-s...

compression may be, more advantageouslyja-hjan a pa mof an le-compound machin s, eachidnirenzx romza..singleiicrankninnand yet: saidsnompnessorsi are-.sorarranged,thatiunbalanoe inedrivineloadiss never yeryigre ti d e. :to;the.unloadingese ueneev provided; Each:oftheitwoiconstituentacompresee sorsmas; anAdventageoilsrintereoolen iarraneeei mentpoth fordtself; and iorsthesm chine. asses wholes. An effective du-bricantgcqoling system is; provided... An; extre1nely.icombact;arrangements considering; the...air..; outputnlis: presentediit Thee. driving motormay. lee-rcpt withinstheiprojeetions ona .horizontalmaneof theunaehine as. armhole and,..being..supnorted byitheim n immenrequiresi no. spec al outsidesfoundationas By theire1a ly-uprightarrangement of the lowspressureccv t inders, the overall heightroi,thegnachinerand t-h height of the crankshait.abovejthee-supporting; surface for the machineniay.zbeJieptiatia.Jniniwmum... Condensate, from; thee-331 underaoingii died by .:this -,arrangement,; moreoven.sinceathecdischarges for. the ,condensate.. =are arranged? at: the points C, towardsuwhich the: air. insflowingea through the intercoolers.towards theirrtake tm the high pressure .cy1inders.-tends;.:t0 .entrainrth water and any other liquid condensed ,Qutofsthec air. It will .be noted, .further,-; that the; valves. will be more conveniently accessible, bOth,:ln-1'et"{ and discharge valves and loading andsunloa-dingii controlling valves.

In the modificationof .theinven-tion illustrated in Figs. 9 and 10,:there is: shown a. compound.-..=. compressor having-a lowtpressure cylinders: I I9 and a high pressure cylinder I extending from-1; a base frame I 2I at opposite; sides ofaaivertical i plane and approximately-45.from-a horizontals.

plane. Air is. compressed in:. .the slow i-pressu'r 1; cylinder and discharged to anelintercoolerwfl which is supported by theibaseframe in the:- sameev series of horizontal planeswithmthez cylindersmvv cooler, about cooling .tubes-I 23oexten-ding dongle; tudinally of the intercooleLi-andpasses --thr ougl t: a connection. I 24 'andinlet' valves .I 25 and lid- 130.4..-

creaseirr-pressure inwtheiintercooler 32;. operates 5. the high pressure .cylinder,..where th aims-corntogpclose :the cylinder gvent in the same manner; as..= the aventi-ng means, I01; the. high. pressure :cylinre den-5 explained above, and permit compression in;

one end of the high ,pressureqcylinder. 4.: Onaav pressed again and discharged through-discharge valves I2! and I28 and adischarge connection; I29 to a receiver (not 1.Sh0?WI1-)'.. Reciprooably'tmounted in the lowandihigha-pressure cylins still further, decrease-inrec v r: 'the'-i50e ders are pistons I30 and I31. connected throughi pil t valve 69 operates to ent pressure from their inlet valve opening. devices. 79 and, 80- and permits the inlet valves: in. the low and highspressure cylinders 2 and '4 'to operate in theirunormali:

manner, and thecompressor operates'fully load-.1.

ed; to ':compress: air :and "dischargeit; to there-1t ceiven- Regarding this embodimentof the invention, it i will be noted that each of thefour pistons 45, 2451.3; and 46;:46-isrconnected through a separate con:- necting .rod-atorascommon' crankpin. Each cylin'--- dersl'iasiaprosshead. guide souarranged that the thrust-s orthe :severali'crossheads are taken withinrrthamain1:frame..=ot the machine: The four cylinders are independently mounted-on the main fram-e-and are subjeoted tomo thrusts growing outxofithe operation.ot thesmachine except Iongitudinally of the studs or holding "bolts which may: be-used tOJfiX thBM to the frame. Since the A severalr cylinders ares arranged "at substantially-- 60?;iang1es 110 each other; and .Lsince each cylin de'mis double-acting: and: designed 'sothat the worls done 1 is :substantially the samein' each cylinderra very=uniform driving-loadis provided-e There isi provided moreover, the equivalent of 1 .;base frame beneath the intercooler and formed integral with the base frame is a support I4I on which a motor I42"is rigidly mounted; and the: m-otors rotor I43 is keyed to the end.ofthe-crankshaft I36. As-in the embodiment first-described: itwillbe noted that thehorizontalintercooler in the same horizontal planes with" the low pressure cylinder, and the motor beneath"the intercooler, are employed.

In'the modification-of theinvention-illustrat ed in Figs. 11 and 12,"a 10w pressure cylinder I I8 and a high pressure'cylinder *IZ'EI are-supported" by a base'frame I2I in the same-manneras in the modification illustrated in =Fig'S'u 9 and 101 Air is compressed-in the low pressure cylinder and discharged 'throughara 1 connection-:1 45 to-achamber I46 extending along the top of the in-' tercooler section I41 of an intercooler-radiator, generally designated I48. An opening I49 is provided along the bottom of the chamber I46 through which compressed air passes to tubes I50 supported in a vertical position, and through the tubes to a chamber I5I extending along the bottom of the intercooler section I41. A discharge passage I53 conducts compressed air from the lower chamber I5I to the high pressure cylinder through inlet valves I and I26, where the air is compressed again and discharged through discharge valves I21 and I28 and a connection I29 to a receiver (not shown). The intercooler-radiator I48 is provided with a radiator section I55 through which a cooling fluid circulates from an upper chamber through vertical tubes to a lower chamber in the same manner as in the section through which the compressed air passes. Connected to the chamber in this radiator section is a pipe I55 for conducting cooling fluid to a fluid pump i51 that forces the cooling fluid through a pipe I53 to a chamber I69 formed in the walls of the low pressure cylinder. A pipe IBl chamber IE9 at its upper level to a point in a chamber I62 formed in the walls of the high pressure cylinder, and a pipe I63 connects an upper point in the chamber I62 to the upper chamber of the radiator section.

Reciprocably mounted in the low pressure cylinder and the high pressure cylinder are pistons I30 and Ni connected by piston rods I32 to crossheads I33 reciprocably mounted in crosshead guides I34 formed within the base frame. Connecting rods I35 connect the crossheads to a common crank shaft I36. The crank shaft is journaled at one end in a bearing I31 carried by a plate I38 attached to the side of the base frame, and is journaled at its other end in bearings I39 and I40 supported by the base frame. Keyed to the end of the crank shaft beneath the intercooler is a drive pulley I64 which may be driven from a source of power not shown.

Attached to the side of the intercooler-radiator opposite the compressor is a frame 555 supporting cooling fans I66 and IE1 on shafts E63. The cooling fans are driven by a pulley I10 keyed to a reduced extension of the crank shaft I36, through belts Ill and pulleys E12 keyed to the shafts I68 supporting the fans. A pulley I13 driven from the pulley I10 through a belt I14 drives the fluid pump I51.

In the operation of this modification of the invention, air is compressed in the low pressure cylinder and discharged to the chamber I46 in the air cooling section of the intercooler-radiator. The air flows from the chamber I through the vertically supported cooling tubes I50 to the chamber I5I extending along the bottom of the air cooling section of the intercoolerradiator, and from the chamber I5I through passage I53 to the high pressure cylinder, Where it is compressed again and discharged through the discharge pipe I29. Cooling water is pumped from the bottom of the radiator section I55 through pipe E56, pump I51 and pipe I58 to the chamber I60 in the low pressure cylinder, and from chamber I60 through pipe I6! to the chamber I62 in the high pressure cylinder, then through pipe I63 to the top of the radiator section and through the vertical cooling tubes and back to the bottom chamber. Air is forced over the cooling tubes in the intercooler-radiator and over the low and high pressure cylinders by lower connects the through belts I1I.

The presence of certain features common to the embodiments previously described, together with certain features individual to this particular embodiment, will be apparent.

While there are in this application specifically described several forms which the invention may assume in practice, it will be understood that these forms of the same are shown for purposes of illustration and that the invention may be further modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure'by Letters Patent is:

1. In combination, in a pump, a crankcase rotatably supporting a horizontal crankshaft having a single crankpin, a low pressure cylinder supported by said crankcase in a position with its axis making a substantial angle with the horizontal, a low pressure piston in said low pressure cylinder operatively connected with said crankpin, a high pressure cylinder supported by said crankcase with its axis making a substantial angle with the plane which includes the axis of rotation of said crankshaft and the axis of the low pressure cylinder, a high pressure piston in said high pressure cylinder operatively connected with said crankpin, and an intercooler supported by said cylinders and including a casing extending horizontally and substantially wholly in horizontal planes above the lowermost point in said low pressure cylinder whereby a driving motor for said crankshaft may have its casing supported by said crankcase above the bottom of the latter and below said intercooler.

2. In combination, in a pump, a crankcase rotatably supporting a horizontal crankshaft having a single crankpin, a pair of low pressure cylinders supported by said crankcase in positions such that their axes make at least substantially equal angles with the vertical plane in which the axis of rotation of the crankshaft lies, a pair of high pressure cylinders supported by said crankcase in positions such that their axes make at least substantially equal angles, different from the angles made by said low pressure cylinders. with the vertical plane in which the axis of'rotation of said crankshaft lies, pistons one in each of said cylinders and each operatively connected with said crankpin, said several cylinders further so disposed that a single plane to which the axis of rotation of said crankshaft is perpendicular intersects each of said cylinders, and intercoolers, one for the cylinders at each side of said vertical plane, receiving the discharges from the low pressure cylinders and delivering fluid to said high pressure cylinders.

3. In combination, in a pump, a crankcase rotatably supporting a horizontal crankshaft having a single crankpin, a pair of low pressure cylinders supported by said crankcase in ositions such that their axes make acute angles with the vertical plane in which the axis of rotation of the crankshaft lies, a pair of high pressure cylinders supported by said crankcase in positions such that their axes make at least substantially equal angles with the vertical plane in which the axis of rotation of said crankshaft lies, the last mentioned angles greater than the acute angles made by the axes of said low pressure cylinders with said vertical plane, pistons one in each of said several cylinders and each operatively connected with said crankpin, said several cylinders the fans I66 and I61 driven from-the pulley I10 further so disposed that at least one plane to which the axis of rotation of said crankshaft is perpendicular intersects each of said cylinders, and intercoolers, one for the cylinders at each side of said vertical plane, receiving the discharges from the low pressure cylinders and delivering fluid to said high pressure cylinders, said intercoolers arranged in line with each other.

4. In combination, in a pump, a crankcase rotatably supporting a horizontal crankshaft having a single crankpin, a pair of low pressure cylinders supported by said crankcase in positions such that their axes make acute angles with the vertical plane in which the axis of rotation of the crankshaft lies, a pair of high pressure cylinders supported by said crankcase in positions such that their axes make at least substantially equal angles with the vertical lane in which the axis of rotation of said crankshaft lies, the last mentioned angles greater than the acute angles made by the axes of said low pressure cylinders with said vertical plane, pistons one in each of said sever-a1 cylinders and each operatively connected with said crankpin, said several cylinders further so disposed that at least one plane to which the axis of rotation of said crankshaft is perpendicular intersects each of said cylinders, and intercoolers, one for the cylinders at each side of said vertical plane, receiving the discharges from the low pressure cylinders and delivering fluid to said high pressure cylinders, said intercoolers arranged in line with each other and at least largely in substantially the same series of horizontal planes with said low pressure cylinders.

5. In combination, in a pump, a crankcase rotatably supporting a horizontal crankshaft having a single crankpin, a pair of low pressure cylinders supported by said crankcase in positions such that their axes make acute angles with the plane perpendicular to the base of said crankshaft in which the axis of rotation of the crankshaft lies, a pair of high pressure cylinders supported by said crankcase in positions such that their axes make at least substantially equal angles with the aforesaid plane in which the axis of rotation of said crankshaft lies, the last mentioned angles greater than the acute angles made by the axes of said low pressure cylinders with said plane, pistons one in each of said cylinders and each operatively connected with said crankpin, said several cylinders further so disposed that at least one plane to which the axis of rotation of said crankshaft is perpendicular intersects each of said cylinders, and intercoolers, one for the cylinders at each side of said vertical plane, receiving the discharges from the low pressure cylinders and delivering fluid to said high pressure cylinders, said intercoolers arranged in line with each other and disposed substantially parallel to the axes of the high pressure cylinders and'at least largely in substantially the same series of horizontal planes with said low pressure cylinders.

,6. In combination, in a pump, a crankcase rotatably supporting a horizontal crankshaft having a single crankpin, a low pressure cylinder supported by said crankcase in a position with its axis making a substantial angle with the horizontal and also making a substantial angle with the vertical, a low pressure piston in said low pressure cylinder operatively connected with said crankpin, a high pressure cylinder supported by said crankcase with its axis making a substantial angle with the plane which includes the axis of rotation of said crankshaft and the axis of the low pressure cylinder, a high pressure piston in said high pressure cylinder operatively connected with said crankpin, and an intercooler supported by said cylinders and including a casing extending horizontally and at least mainly in horizontal planes above the lowermost point in said low pressure cylinder whereby space is provided for the disposition of a driving motor for said crankshaft beneath said intercooler with the driving shaft of said motor operatively connected with said crankshaft.

7. In a fluid compressor, in combination, a base frame, a crank shaft journaled on said base frame, cylinders mounted on said base frame and having pistons reciprocable therein, a cooling system for said compressor comprising a cooling device supported between said cylinders, said cooling device having a portion for conducting compressed fluid and another portion for conduccting a cooling fluid, means for forcing the cooling fluid from said cooling fluid conducting portion through said cylinders, cooling fans arranged at the side of said cooling device opposite said cylinders for forcing cooling air over the portions of said cooling device and over said cylinders, and means attached to the end of said crank shaft under said cooling device for driving said cooling fans.

8. In a fluid compressor, in combination, a base frame, a crank shaft journaled on said base frame, cylinders mounted on said base frame and having pistons reciprocable therein, a cooling system for said compressor comprising a cooling device supported between said cylinders and having an intercooler portion and a radiator portion, means for conducting compressed fluid through the intercooler portion, means for conducting a cooling fluid from the radiator portion through said cylinders, and means for effecting a flow of cooling air through said cooling device and over said cylinders.

FRANK A. HALLECK.

Patent' N0. 2, 5 2,555-

CERTIFICATE OF CORRECTION. e

M r h '2, wk FRANK A. HALLECK.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line 25, for "Fig. 6" read "Fig. 5"; page 2, first column, line 52, for "way" read --was-; page 5, second column, line 5556, for"condtlccting" read --conducting-; and that the said Letters Patent should beread with this correction therein that the same may conform to the record of the case in the Patent Office. I

Signed and sealed this 2911; day of June, A. D. 19%.

Henry v an Arsdale',

(Seal) 7 Acting Commissioner of Pat fint'ss 

